The Telenor Research Centre was located in Kjeller until 2001, when the majority of employees moved to Fornebu on 23 November.

Akershus University College was opened in autumn 2003 at Telenor's previous location.

The array at NORSAR was one of the first European nodes of the ARPANET, the precursor to the Internet.

The Netherlands supplied the uranium and Norway the heavy water.

On 9 September 2006, the reactor suffered a "contained" leak which forced it to shut down for three weeks for repairs.